Perhaps you should try some spelling variations:
theo hieu » theo chieu, theo tieu, thien hieu
hieu lang » chieu sang, hieu quang, nhieu tang
bean song » bang song, phan song, gian song
manh toan » thanh toan, anh tuan, tinh toan
anh tang » anh bang, anh dang, anh nang
tang cua » mang cua, hang cua, tang luan
ban song » bang song, ban cong, ban tong

You may be able to get more results by adjusting your search query.

• Performing a fuzzy search may retrieve terms with similar spellings: theo hieu lang - anh tang cua ((ban song) OR (bean song)) ((manh toan) or (van ban)) ban~.
• If you are trying to use Boolean operators, they must be ALL CAPS: theo hieu lang - anh tang cua ((ban song) OR (bean song)) ((manh toan) OR (van ban)) ban.
• The words AND, OR and NOT may confuse the search; try adding quotes: "theo hieu lang - anh tang cua ((ban song) OR (bean song)) ((manh toan) or (van ban)) ban".
• Adding a wildcard symbol may retrieve word variants: theo hieu lang - anh tang cua ((ban song) OR (bean song)) ((manh toan) or (van ban)) ban*.